Narrative:

Descending into sjc, we had been cleared visual approach to runway 30L. Approach control had just previously called low traffic passing off to right. Just as this was occurring, we received a TCASII TA. This traffic also was below us and we appeared to be on a collision course. This TA quickly turned into an RA. I immediately executed the commanded escape maneuver which called for changing my descent of 1800 FPM into a climb of 1200 FPM. My altitude was approximately 6500 ft MSL at initiation of RA. At approximately 7200 ft MSL clear of traffic was announced on TCASII as aircraft passed directly below us by 500 ft. I believe a midair collision would most likely have occurred had the TCASII not been installed -- operational and utilized. No TA was ever given to us by ATC (on this traffic) during this entire maneuver. Supplemental information from acn 368042: as we looked we received a TA at 12 O'clock on the TCASII. The captain was flying so when we got the RA he began the climb as called for by the TCASII. I saw the plane and did not think we would clear so I said pull up. The captain increased the climb rate and we passed over the target. The other plane was a single engine, yellow and white, high wing aircraft. Bay approach said they were not painting the other plane.

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Original NASA ASRS Text

Title: NEAR HIT BY S80 ON XING SMA AT WRONG ALT FOR DIRECTION OF FLT. ATC WAS NOT PAINTING TFC, HAD CALLED TFC ON ANOTHER ACFT JUST PRIOR TO THIS EVENT. ATC SAID THEY WEREN'T PAINTING THE SECOND ACFT. ANOTHER SAVE BY TCASII, QUOTE FROM CREW.

Narrative: DSNDING INTO SJC, WE HAD BEEN CLRED VISUAL APCH TO RWY 30L. APCH CTL HAD JUST PREVIOUSLY CALLED LOW TFC PASSING OFF TO R. JUST AS THIS WAS OCCURRING, WE RECEIVED A TCASII TA. THIS TFC ALSO WAS BELOW US AND WE APPEARED TO BE ON A COLLISION COURSE. THIS TA QUICKLY TURNED INTO AN RA. I IMMEDIATELY EXECUTED THE COMMANDED ESCAPE MANEUVER WHICH CALLED FOR CHANGING MY DSCNT OF 1800 FPM INTO A CLB OF 1200 FPM. MY ALT WAS APPROX 6500 FT MSL AT INITIATION OF RA. AT APPROX 7200 FT MSL CLR OF TFC WAS ANNOUNCED ON TCASII AS ACFT PASSED DIRECTLY BELOW US BY 500 FT. I BELIEVE A MIDAIR COLLISION WOULD MOST LIKELY HAVE OCCURRED HAD THE TCASII NOT BEEN INSTALLED -- OPERATIONAL AND UTILIZED. NO TA WAS EVER GIVEN TO US BY ATC (ON THIS TFC) DURING THIS ENTIRE MANEUVER. SUPPLEMENTAL INFO FROM ACN 368042: AS WE LOOKED WE RECEIVED A TA AT 12 O'CLOCK ON THE TCASII. THE CAPT WAS FLYING SO WHEN WE GOT THE RA HE BEGAN THE CLB AS CALLED FOR BY THE TCASII. I SAW THE PLANE AND DID NOT THINK WE WOULD CLR SO I SAID PULL UP. THE CAPT INCREASED THE CLB RATE AND WE PASSED OVER THE TARGET. THE OTHER PLANE WAS A SINGLE ENG, YELLOW AND WHITE, HIGH WING ACFT. BAY APCH SAID THEY WERE NOT PAINTING THE OTHER PLANE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.